This invention relates generally to medical devices for supporting extremities and more specifically to an inflatable cushion for elevated support of an extremity.
Elevation of an extremity has several well known therapeutic applications, including reducing swelling by encouraging gravitational flow of blood out of the extremity. Moreover, supporting the extremity away from other surfaces, such as a bed mattress, prevents the occurrence of bed sores and promotes the healing of damaged tissue. In the past, elevation of the extremities has been accomplished primarily through the use of pillows or cushions, used individually or stacked to achieve an appropriate elevation. Air mattresses, padded boots and padded socks have been used to cushion the extremity at a pressure point (e.g., the back of the heel or the elbow) to prevent the occurrence of bed sores.
Bed sores are a common problem among patients, and particularly older patients, who are confined to bed with a limited ability to move. Pillows, padded boots and padded socks are relatively soft and deformable, but they lack resiliency so that the weight of the extremity tends to be supported over a small area of the extremity, causing a pressure point. Although air mattresses are resilient, a disproportionately high amount of its weight is supported over a small area of the extremity such as the heel or elbow. Other devices, such as small inflatable annular rings can support the heel or elbow away from the bed, but these devices still support the weight of the extremity over such a small area that circulation around the heel or elbow often is cut off. The existence of the pressure point causes pain in the extremity because of the concentration of force on a small surface area of the extremity. The presence of a pressure point leads to break down of the skin tissue causing a bed sore, and the presence of an open wound raises the potential for infection.
If the extremity can be moved the pressure point may be changed, but the pain will only recur in time. Moreover, movement of the extremity can cause the extremity to fall off the pillows or cause a stack of pillows to fall over. This is particularly a problem when a patient must have his extremity elevated for an extended period of time and changes position in bed periodically to maintain comfort. In addition, the patient's skin may have an allergic reaction to the material of the pillow, padded boot or padded sock.